Phase formation and characterization of the SrBi2Ta2O9 layered-perovskite ferroelectric

Autor: Michael O. Eatough, Celeste A. Drewen, Bernadette A. Hernandez, Mark A. Rodriguez, Timothy J. Boyle, Raplh G. Tissot, Catherine D. Buchheit
Rok vydání: 1997
Předmět:
Zdroj: Integrated Ferroelectrics. 14:201-210
ISSN: 1607-8489
1058-4587
DOI: 10.1080/10584589708019993
Popis: The Sr-Bi-Ta-O system is of interest for thin-film non-volatile ferroelectric memories. A better understanding of the process by which the perovskite phase forms can provide insight for improved processing of this ferroelectric compound. We have prepared thin-films by a chemical method using Sr-acetate, Bi-acetate and Ta-ethoxide; cation ratios were ∼1:2:2 for Sr, Bi, and Ta, respectively. Results of in-situ crystallization studies using High-Temperature Grazing-Incidence X-ray Diffraction (HTGIXRD) have demonstrated that a fluorite structure, forming in the ∼600 – 700 °C range, acts an intermediate phase prior to the crystallization of the perovskite. Additional samples with cation ratios of –1:0.8:2 were also investigated. Results for samples prepared with the 0.8 Bi content indicated that a pyrochlore phase forms which contains a substantial deficiency in Bi compared to the composition of the perovskite phase. The structures of the pyrochlore and fluorite phases and their relation to the forma...
Databáze: OpenAIRE